There exists a need for improved and simplified control in a RMS voltage regulation system, as may be employed, illustratively, in power supplies for CATV and broadband communication distribution systems, battery charging systems, and the like. RMS determinations are of vital importance in all alternating current and pulsed direct current power systems, and root mean square (RMS) computations are and remain the principal practical means of determining the effective "quantity" of effective AC electricity provided in the circuit, whether measured in voltage or current.
Heretofore, RMS control systems have been limited in one and usually several respects in connection to power sources, as, for example, incompatibility with both AC and pulsed DC outputs and like incompatibility with diverse pulse width modulation switch topologies or systems. Further such prior art systems used analog feedback control to provide RMS regulation.
Similarly, prior techniques have not been able to reliably provide an accurate trapezoidal output wave as well as achieve precise RMS voltage regulation with maximum conversion efficiency. A conventional analog approach to RMS voltage regulation is to use a PWM amplifier that has feedback to force the output wave to be proportional to a reference signal. This requires that the crest value be controlled as well as the pulse rise (fall) time. Also the procedure does not lend itself readily to digital control techniques. The result is greater switching loss. Also analog PWM control is less flexible than digital control and more expensive to implement.
While analog pulse width modulation systems feeding output L-C and like circuits with conventional power inputs may be employed, there are environments in which digital loop control and pulse crest width modulation would be desirable.